Step 6: Vehicle wire harness and switch

Step 7: Final Product

Here's the results:

The bulldog hood ornament is on just about every mack truck across the globe. I managed to get one, mount it on a jeep, and led lights for eyes. This instructable explains the led mounting procedure in non technical terms so your rig (or bike, kayak, dune buggy, etc) can have glowing eyes.

Step 1: Procurement and Parts

Bulldog Procurementthe mack truck bulldog hood ornament is available for purchase on ebay or onlineI purchased it 6 years ago at a tour of the mack truck factory for 30 dollars at the time. it might also be a good idea to find a big scrapyard and check.

ledsi used 3mm (aka T1) bright led's check mouseror digikeyfor the brightest ones available for the color you choose. 5mm led's would be too big and look dorky. its also good to use clear led's so that when the eye's are off they look like part of the silver structure, not little red dots. resistors can be purchased at radioshack or along with the order.

Current Limiting Resistorthe resistor value you use is dependant on the led used and the power supply for your vehicle. for an led with a vd or forward voltage of 2.6 volts and an id or forward current of 20 milliamps (see datasheet image) and a vehicle with a 12v supply here's the procedure for determining the correct resistor value

(vehicle voltage - vd) = vdrop so:12v-2.6v= 9.4V= vdrop

using R=(V/I) substitute values in place R= 9.4V/ 20 ma = 9.4/ .02so R = 470 ohmsthe power dissipated across the resistor is calculated from P=IV.02*9.4=.188 Watts , so a 1/4 watt resistor (common at radioshack or real electronic parts store) is ok to use. chances are a 1/2 watt resistor might be better suited as the resistor wont be able to dissipate much heat into epoxy.

well they say that its illegal because that it would signify a taillight, but i think that people will see 2 bright white headlights before they see 2 little red lights. especially through their car mirror. he should be ok, and unless you look closely in the mirror, its more of a close up decoration than a far away one.

wowsers, i didnt realize that. hmmmm..... well, i was thinking of modifying the led's to blink the left eye when turning left and the right one when turning right. what colors would look equally bad-ass as red led's on a red jeep. i guess white led's would look decent., orange is too close to red

If you drive fast enough, the red will appear green because of the doppler effect, You just need a bit less then 15% lightspeed for that or 45.000 kilometers per second. You see, that red aint a problem if your car gots enough horses.

Orange is perfectly fine to have on the front, look at your front blinkers for example, but i think you should be fine I'd just leave them until you get pulled over for it. At worst you would get an actual written warning.

An anecdote. My grandfather used to say (living in Idaho) "It's cold enough to freeze the balls off a brass bulldog!". A few years back my dad acquired a Mack bulldog, so we sent it to the shop for a copper dip (brass dip isn't what you think it is) for Fathers' Day. They tried to sandblast the chrome off and found the sand blew through the pot metal the dog was made of... They acquired a replacement, bead blasted instead, dipped it in copper, and threw in a nice custom wood base (for our time and trouble). It sat on Dad's desk a year or so, then the house burned down... I like this, the led eyes are pretty cool. Forgive me for not wanting a Mack bulldog near my house ever again :)

That's pretty cool. Definitely one I'll keep in mind for my next beater. If you want to get the noise down inside your jeep, try insulating the hood. There are specific materials (sort of like a blanket with a sticky back) that will really cut down on the noise at highway speeds. Check with your local auto supply house (or a junkyard) and pick some up. It's fireproof and all that good stuff.

thanks for the comment! the bulldog is held in place by a 5/8 inch threaded bolt, you probably don't need to weld it (it also is aluminum, so welding aluminum to steel would be a pain), but if your going to buy one, check your local scrap yard, they normally can order the parts or find it for you a lot cheaper than they would be available online. -Dane